Microphone for apparatus to check the rate of timepieces



March 27, 1962 F. MART! ETAL 3,026,708

MICROPHONE FOR APPARATUS TO CHECK THE RATE OF TIMEPIECES Filed July 22,1958 2 Sheets-Sheet 1 3 78 5 15 9b Q .90 9b: 7 8 8 A 6 INVENTORSFre'cle'ric Marpb' geolyes .Bramsckum'y 1km Schaad Y M,W

ATTORNEYS MICROPHONE FOR APPARATUS TO CHECK THE RATE OF TIMEPIECES FiledJuly 22, 1958 March 27, 1962 F. MART] ETAL 2 Sheets-Sheet 2 WYW 5 $2 A 2m Mmm m M w n HWBJY a 5 6 W G iJ-nited States Patent 3,026,708MTQROPHONE FOR APPARATUS TO CHECK THE RATE OF TIMEPIECES Frederic Marti,Georges Braunschweig, and Jean Schaad,

aii of 165 Rue Numa-Droz, La Chaux-de-Fonds, Switzerland Filed July 22,1958, Ser. No. 750,237 Claims priority, application Switzerland Aug. 13,1957 1 Claim. (Cl. 73-6) This invention relates to improvements in theconstruction of microphones for apparatus to check the rate oftimepieces or timepiece movements.

One object of the invention is to provide a microphone of this charactercomprising a support, a case enclosing a piezoelectric device and asliding clamping member adapted to co-operate with a fixed clampingmember for removably securing a timepiece to be checked on theobservation surface of said case.

Another object of the invention is to provide an improved slidingarrangement whereby the sliding clamping member will be adapted to slidesubstantially over the whole length of the observation surface of themicrophone case.

Still another object of the invention is to provide an improved slidingarrangement in which the sliding clamping member is mounted on a springloaded slide which is guided in two side guides extending longitudinallyto a rectangular microphone case on both sides of the piezoelectricdevice enclosed therein.

With these and other objects in view, the invention consists of certainnovel features of construction as will be more fully described, andparticularly pointed out in the appended claims.

The accompanying drawings represent, by way of example, a preferredembodiment of the invention.

FIGURE 1 is a longitudinal section of the microphone.

FIGURE 2' is a cross section on line 11-11 of FIGURE 1.

FIGURE 3 is a perspective view of the microphone case, in which someparts have been removed or broken to show the sliding arrangement.

FIGURE 4 is a partial cross section on line IV-IV of FIGURE 1.

FIGURE 5 is a partial cross section on line V-V of FIGURE 1.

The microphone represented comprises a support 1 composed of ahorse-shoe shaped base 1a, an upright 1b made integral with the base 1a,and a hollow horizontal supporting arm 2 fixed to the upright 1b anddesigned for the passage of a flexible cable 3 to connect electrically apiezoelectric device 4 enclosed in a rectangular case 5 to an apparatus,not shown, to check the rate of timepiece mpvements.

On a reduced diameter extension 2a of the hollow horizontal supportingarm 2 is rotatably mounted an arm 6 carrying a fixed hollow shaft 7extending perpendicularly to the axis of arm 6. On said shaft 7 ispivoted by means of side flanges 8, the lower piece 9a of a metallicframe which forms the bottom and the body of case 5. Said metallic framecomprises also an upper piece 9b which forms the cover of the case 5.The upper surface of this cover 9b is the observation surface of themicrophone.

The two pieces 9a and 9b are removably secured to each other by means ofscrews (not shown). The lower piece 9a is formed at its front portion,opposite to the supporting arm 2, with a rectangular recess 10 withinwhich is lodged the piezoelectric device 4. This recess 10 is closed bya cover 11 which extends above the upper surface of the lower piece 9a;the latter is formed in prolongation of the cover 11 up to its back endwith a wide longitudinal rib 9a. Furthermore, the upper piece 9b whichforms the cover of the case is provided with two side flanges 9b whichform, together with the cover 1 1 pf the recess 10 and the central rib9a, two side channels 12 designed for guiding the two U-shaped edges ofa slide 13; this slide .13 carries a jaw 14 having two teeth 14a and 14band a handling finger 14c adapted to slide in a longitudinal slot 15 inthe median portion of the piece 9b which forms the observation surfaceof the microphone. Both channels 12 extend from one end to the other ofthe rectangular case, whereby it is made possible to shift the slidingjaw 14 almost over the whole length of the case 5 and therefore to fixon the observation surface timepieces in a very large range of sizes.

Two coil springs 16 are lodged in the U-shaped edges of slide 13 andattached at one end to pins secured to the front end of piece 9b and atthe other end to the back end of the slide 13, so as to constantly pullthe jaw 14 towards the front end of the case. A second jaw 17 is fixedto the bottom of the recess 10' and is provided with two teeth 17a and17b which extend outwardly through apertures in the covers 11 and 9b.The cover 9b bears at its back end two fingers 18 designed to facilitateoperation with a single hand of the sliding jaw 14 against the action ofthe coil springs 16.

Through an aperture in one of the side flanges 9b of the upper piece 9bpasses a push-button 19 pressed by a spring 20 and designed to lock thesliding jaw 14 in a position remote from the fixed jaw 17; to this end,the push-button 19 engages with a side slot 21 in the U- shaped edge ofthe slide 13. By so locking the sliding jaw 14 it is made possible tosimply lean a timepiece to be checked against the fixed jaw 17 withoutclamping it between said fixed jaw 17 and sliding jaw 14, thusincreasing the possibilities of using the microphone for checking therate of big sized timepieces.

What is claimed is:

Apparatus for clamping and holding a timepiece to check its rate, saidapparatus comprising a support stand, a generally rectangular caseadjustably mounted on said stand and enclosing at one end a soundtransducer, said case having a track along its length extending from oneend to nearly the other end, and leaving an open slot in the top of saidcase, a mating slide member fitted in said track and having anupstanding clamp portion extending through said slot, said slide memberhaving two bent-over edges on opposite sides, a stationary clamp positioned at one end of said track and cooperating with said upstandingclamp to hold a timepiece against said case, said stationary clampextending freely through the top of said case down to said soundtransducer, spring means urging said slide member toward said stationaryclamp, said spring means comprising a pair of tension springs recessedin the bent-over edges of said slide member, said upstanding clampcomprising a bifurcated bracket fastened to said slide member, saidslide member being captive in said track, and finger holding meansprovided on said case and on said slide member, whereby said 3 membercan be manipulated by an operator using one hand and a wide range oftimepiece sizes can be accommodated.

References Cited in the file of this patent UNITED STATES PATENTSStarbuck Nov. 7, 1905 4 Thompson Ian. 4, 1927 Franks et a1. May 24, 1949Mtongelli et a1 Apr. 17, 1951 Mongell-i May 4, 1954 FOREIGN PATENTSSwitzerland Aug. 16, 1947 Great Britain n-- May 16, 1956

